Various types of electrodes, includes subcutaneous and supracutaneous, find use in the medical arts. Some are configured to receive micro-voltage signals from a biological organism, while others are configured to convey electrical signals from an external system to the organism.
Subcutaneous electrodes configured to impart an electrical signals to an organism may be required to operate under varied voltage and current ranges. The vast majority of modern electrodes used in biomedical applications are designed to transfer a low amount of energy. However, as the delivered energy increases, there is a higher probability of ionization and a risk of arcing that results in insufficient electrical delivery into a resistive load or biological tissue. The majority are simply not designed to function optimally under high voltage, high current paramaters.
Furthermore, while some existing electrode technologies include one or more retention features, they are often not sufficient to retard the electrode from propagating both deeper or shallower within the tissue of interest. Even with a retention features, known electrodes may not be configured to place the tip sufficiently deep into the tissue, while simultaneously remaining insulated from the focused electrical discharge at the tip.
More specifically, prior art apparatus and methods for electrical tissue stimulation involved using a needle, an alligator clip, or short barb to deliver the energy to the biological tissue of interest. Prior art technologies limited the scope of applicable use for numerous reasons. First, the typical probe depth was limited to superficial surfaces and would not allow for varied depth implantation. Also, electrodes previously used were often very thin point sources that undesirably increase the rate of charge distributed towards the very tip of the probe, thus increasing the possibility of ionization and arcing at a spatial location. Lastly, prior art technologies did not provide a satisfactory means to stabilize the electrode in place and thereafter prevent it from sliding further into or out of the biological medium.
As a result, there exists a need in the art for a high voltage capable implantable electrode having retention features and geometries suitable for deep tissue implantation.